Official Discussion issued by the National Hurricane Center

Zeta (AL282020) DATA RELEASED: 10/27/2020 4:00:00 AM UTC

Copy of official data

Tropical Storm Zeta Discussion Number  11
NWS National Hurricane Center Miami FL       AL282020
400 AM CDT Tue Oct 27 2020

Satellite imagery and surface data from Mexico indicated that Zeta 
made landfall along the coast of the Yucatan Peninsula just north of 
Tulum near Ciudad Chemuyil just before 0400 UTC.  A WeatherFlow 
observing site just south of Ciudad Chemuyil reported light winds 
and a minimum pressure of 978 mb.  Another WeatherFlow site near 
Playa del Carmen reported a one-minute sustained wind of 64 kt with 
a gust to 76 kt.  Hurricane-force winds gusts were also reported on 
Cozumel.  Since the time of landfall, the center of Zeta has moved 
inland over the northern portions of the Yucatan peninsula.  Some 
weakening has likely occurred, so the initial intensity has been 
reduced to 60 kt.  Zeta is forecast to emerge off the northern coast 
of the Yucatan peninsula over the southern Gulf of Mexico shortly 
after 1200 UTC today.  Although some slight additional weakening is 
possible while the center moves overland early this morning, 
environmental conditions consisting of low vertical wind shear and 
warm water over the southern Gulf of Mexico should allow for 
re-strengthening over the next 24 hour or so. By the time Zeta moves 
over the northern Gulf, cooler waters and increasing shear are 
likely to cause the hurricane's intensity to level off or perhaps 
weaken slightly before landfall.  Regardless, Zeta is expected to be 
at or near hurricane intensity at landfall. Given Zeta's 
acceleration before landfall, strong winds are likely to spread well 
inland along northern Gulf coast Wednesday night.  The new NHC 
intensity forecast is again similar to the previous one, and is 
little above the model consensus, in best agreement with the HWRF 
model. 

Zeta is moving northwestward or 305/12 kt.  There has been no change 
to the track forecast reasoning. The hurricane will move around the 
southwestern portion of a mid-level ridge center east of Florida.  
By tonight, a vigorous shortwave trough ejecting out of the 
southwestern United States will cause Zeta to turn northward, and 
accelerate northward to north-northeastward on Wednesday and 
Thursday. This will bring Zeta across the north-central Gulf coast 
late Wednesday and over the southeastern United States on Thursday.  
The track guidance remains in good agreement with only some slight 
timing differences.  The updated NHC track forecast is again very 
similar to the previous advisory and close to the various consensus 
models.  The new track, intensity, and wind radii forecasts 
necessitate the issuance of Storm Surge, Hurricane, and Tropical 
Storm Warnings for a portion of the northern Gulf coast. 


KEY MESSAGES:

1. Tropical storm conditions will continue in portions of the 
northern Yucatan Peninsula of Mexico through this morning. Heavy 
rainfall is expected across the Yucatan Peninsula, the Cayman 
Islands, and western Cuba today, which could lead to flash flooding 
in urban areas.

2. Hurricane conditions and life-threatening storm surge are 
expected along portions of the northern Gulf Coast by late 
Wednesday, and Storm Surge and Hurricane Warnings are in effect. 
Residents in the watch areas should follow any advice given by 
local officials.

3. Between tonight and Thursday, heavy rainfall is expected from 
portions of the central U.S. Gulf Coast into the southern 
Appalachians, and Mid-Atlantic States near and in advance of Zeta. 
This rainfall will lead to flash, urban, small stream, and minor 
river flooding.


FORECAST POSITIONS AND MAX WINDS

INIT  27/0900Z 21.0N  88.4W   60 KT  70 MPH...INLAND YUCATAN
12H  27/1800Z 22.3N  90.1W   65 KT  75 MPH...OVER WATER
24H  28/0600Z 24.4N  91.5W   75 KT  85 MPH
36H  28/1800Z 27.5N  91.2W   75 KT  85 MPH
48H  29/0600Z 31.7N  88.0W   55 KT  65 MPH...INLAND
60H  29/1800Z 36.5N  81.0W   30 KT  35 MPH...INLAND
72H  30/0600Z 40.3N  70.0W   45 KT  50 MPH...POST-TROP/EXTRATROP
96H  31/0600Z...DISSIPATED

$$
Forecaster Brown